Answer:
Step-by-step explanation:
Socratic had the answer on there I think 
 
        
             
        
        
        
Answer:
10·b = 60
Step-by-step explanation:
The given system of equation is presented as follows;
5·a + 5·b = 25...(1)
-5·a + 5·b = 35...(2)
Given that the coefficient of a in equation (1) is equal in magnitude but opposite in sign to the coefficient of 'a' in equation (2), to eliminate the variable 'a' when using the elimination method, we add both equations as follows;
5·a + 5·b + (-5·a + 5·b) = 25 + 35 = 60
5·a - 5·a + 5·b + 5·b = 60
5·a - 5·a = 0
5·b + 5·b = 10·b
∴ 5·a - 5·a + 5·b + 5·b = 60 = 0 + 10·b = 10·b
∴ 10·b = 60
 
        
             
        
        
        
Answer:
See below. 
Step-by-step explanation:
1)
So we have: 

This can be interpreted as: 
"There exists a natural number <em>x</em> and an integer <em>y</em> such that x² is equal to y²."
2) 
So we want even numbers are in the set of integers. 

This is interpreted as: 
"The set of even numbers (2n such that n is an integer) is in the set of integers"
 
        
             
        
        
        
Answer:
h = 6
Step-by-step explanation: